Abstract
Introduction
Biomechanical studies of the rugby union scrum have typically been conducted using scrum machines (Milburn, 1990; Preatoni et al., 2013), but a biomechanical analysis of rugby union scrummaging (team A against team B) is still lacking. The aim of this study was to analyse kinematic and kinetic variables during contested scrummaging in three different engagement conditions designed in part to modify the loading conditions on players: Crouch-Touch-Pause-Engage (CTPE, in use prior to 2012/13 season), Crouch-Touch-Set (CTS, current) and Touch-Held (TH, test).
Methods
Sixteen forward packs (n=128 players) from two playing categories (International and Professional Club) performed repeated scrum trials, outdoors on natural turf, following instruction in each of the experimental conditions. Two scrums per condition per team (8 teams, 48 scrums in total) were analysed. Exerted forces between teams’ front rows were estimated by using pre-calibrated pressure sensors positioned on the right and left shoulders of front row players in team A. Inertial Measurement Units (IMU) were placed on the forehead and C7 of each team’s front row players, and both the overall and single axes accelerations were computed. Multiple camera views allowed the recording and subsequent analysis of player movements, in the primary transverse and sagittal planes of motion.
A control system (Preatoni et al., 2012) executed pre-recorded audio commands to players with consistent timings and synchronised data streams.
Results
Biomechanical variables across the conditions were divided by scrum phases. In general the TH technique reduced the biomechanical loading on players, while there was no difference between conditions in terms of body motions relating to stability. Prior to engagement the TH condition showed a lower set-up distance between front rows versus both CTPE (29%) and CTS (30%). During Engagement, closing speed was reduced in TH compared with CTPE (22%) and CTS (19%). During Initial-Engagement, peak force was lower in TH as opposed to CTPE (24%) and CTS (24%) and overall acceleration peak on C7 was lower (p<0.05) in TH compared with CTPE (20%) and CTS (16%). The average force did not differ between conditions during the Sustained scrummaging phase.
Discussion
In this study the biomechanical demands of contested rugby scrummaging were measured for the first time. The findings are stimulating in terms of injury prevention and performance analysis, proposing biomechanical solutions to minimise potential injury risk and a novel method to evaluate different scrum techniques.
References
Milburn PD. (1990). J Sports Sci, 8, 47-60.
Preatoni E et al. (2012). P I Mech Eng P - J Sports Eng Tech, 226(3/4), 266-273. Preatoni E et al. (2013). Scand J Med Sci Spor, doi: 10.1111/sms.12048.
Acknowledgement
Research funded by the International Rugby Board
Biomechanical studies of the rugby union scrum have typically been conducted using scrum machines (Milburn, 1990; Preatoni et al., 2013), but a biomechanical analysis of rugby union scrummaging (team A against team B) is still lacking. The aim of this study was to analyse kinematic and kinetic variables during contested scrummaging in three different engagement conditions designed in part to modify the loading conditions on players: Crouch-Touch-Pause-Engage (CTPE, in use prior to 2012/13 season), Crouch-Touch-Set (CTS, current) and Touch-Held (TH, test).
Methods
Sixteen forward packs (n=128 players) from two playing categories (International and Professional Club) performed repeated scrum trials, outdoors on natural turf, following instruction in each of the experimental conditions. Two scrums per condition per team (8 teams, 48 scrums in total) were analysed. Exerted forces between teams’ front rows were estimated by using pre-calibrated pressure sensors positioned on the right and left shoulders of front row players in team A. Inertial Measurement Units (IMU) were placed on the forehead and C7 of each team’s front row players, and both the overall and single axes accelerations were computed. Multiple camera views allowed the recording and subsequent analysis of player movements, in the primary transverse and sagittal planes of motion.
A control system (Preatoni et al., 2012) executed pre-recorded audio commands to players with consistent timings and synchronised data streams.
Results
Biomechanical variables across the conditions were divided by scrum phases. In general the TH technique reduced the biomechanical loading on players, while there was no difference between conditions in terms of body motions relating to stability. Prior to engagement the TH condition showed a lower set-up distance between front rows versus both CTPE (29%) and CTS (30%). During Engagement, closing speed was reduced in TH compared with CTPE (22%) and CTS (19%). During Initial-Engagement, peak force was lower in TH as opposed to CTPE (24%) and CTS (24%) and overall acceleration peak on C7 was lower (p<0.05) in TH compared with CTPE (20%) and CTS (16%). The average force did not differ between conditions during the Sustained scrummaging phase.
Discussion
In this study the biomechanical demands of contested rugby scrummaging were measured for the first time. The findings are stimulating in terms of injury prevention and performance analysis, proposing biomechanical solutions to minimise potential injury risk and a novel method to evaluate different scrum techniques.
References
Milburn PD. (1990). J Sports Sci, 8, 47-60.
Preatoni E et al. (2012). P I Mech Eng P - J Sports Eng Tech, 226(3/4), 266-273. Preatoni E et al. (2013). Scand J Med Sci Spor, doi: 10.1111/sms.12048.
Acknowledgement
Research funded by the International Rugby Board
| Original language | English |
|---|---|
| Title of host publication | Book of Abstracts of the 18th Annual Congress of the European College of Sport Science in Barcelona, Spain from 26-29 June 2013 |
| Editors | N Balagué, C Torrents, A Vilanova, J Cadefau, R Tarragó, E Tsolakidis |
| Pages | 249 |
| Number of pages | 1 |
| ISBN (Electronic) | 9788469577868 |
| Publication status | Published - 2013 |
| Event | 18th Annual Congress of the European College of Sport Science - Barcelona, Spain Duration: 25 Jun 2013 → 29 Jun 2013 |
Conference
| Conference | 18th Annual Congress of the European College of Sport Science |
|---|---|
| Country/Territory | Spain |
| City | Barcelona |
| Period | 25/06/13 → 29/06/13 |